"In its Spring 2007 in-person, in-home survey of approximately 26,000 adults (ages 18+), MRI asked whether consumers had seen advertising delivered via various alternative media and, if they had, whether they had “considerable”, “some” or “not much” interest in those advertisements. 49.3% of consumers (who have seen at least one billboard ad) report “considerable” or “some” interest in the ads that appear in this format."- pdf of the press release, MRI newsroom